列车风压对桥梁施工中架桥机受力性能的影响

Influence of Wind Pressure of Operating Trains on Mechanical Performance of the Bridge Erecting Machine in Construction of the Adjacent New Railway

为了研究运营列车行驶中产生的风压对邻近新建铁路施工中架桥机的受力性能的影响,以新建昌景黄铁路客专项目为工程背景,通过建立数值分析模型,分析邻近营业线列车行驶过程中产生的侧向气动力对桥梁施工中架桥机全过程的受力状态的影响。研究结果表明:架桥机1号小车准备取梁时(施工阶段1),主梁2的变形状态受到侧向气动力的影响较明显,变形最大值为4.5 mm;主梁1及主梁2在30~65 m区域内,应力均呈现近似对称分布状态;架桥机1号小车和2号小车准备落梁时(施工阶段2),受到所吊装混凝土梁的影响,侧向气动力对架桥机2根主梁的变形状态均产生了一定的影响,最大差值分别为2.5 mm及3.6 mm;受到混凝土梁自重较大的影响,施工阶段2时侧向气动力对架桥机主梁变形影响较小,然而由于架桥机主梁应力最大值高达263.93 MPa,该阶段结构的安全系数较小,为了保证施工过程中的安全性,应对架梁施工全过程进行实时监控。

In order to study the impact of operating trains on the operating performance of the bridge erecting machine in the construction of adjacent new railways,taking the newly-built Nanchang-Jingdezhen-Huangshan railway passenger dedicated project as the background,through the establishment of a numerical analysis model,the paper analyzes the lateral aerodynamic force generated during the train running near the operating line on the stress state of the whole process of bridge erecting machine in the bridge construction.The results show that the deformation state of the main beam 2 is obviously affected by the lateral aerodynamic force when the No.1 trolley of the bridge erecting machine prepares to take the beam(Stage 1),and the maximum deformation is 4.5 mm.The stress of main beam 1 and main beam 2 are approximately symmetrically distributed in the area of 30-65 m.When the No.1 trolley and No.2 trolley of the bridge erecting machine are preparing to drop the beam(Stage 2),they are affected by the lifting of the concrete beam,and the lateral aerodynamic force has a certain influence on the deformation state of the two main beams of the bridge erecting machine,and the maximum difference is 2.5 mm and 3.6 mm respectively.Due to the large dead weight of the concrete beam,the lateral aerodynamic force has little effect on the main girders of the bridge erecting machine at Stage 2.However,since the maximum stress of the main girders of the bridge erecting machine is as high as 263.93 MPa,the safety factor of the structure in this state is relatively small.In order to ensure the safety during the construction process,real-time monitoring of the whole construction process of the girder is required.